4.9-stable review patch. If anyone has any objections, please let me know. ------------------ From: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> This reverts commit 5d3cf50105d007adc54949e0caeca1e944549723 which is commit 628bd85947091830a8c4872adfd5ed1d515a9cf2 upstream. It does not work properly in the 4.9.y tree and causes more problems than it fixes, so revert it. Reported-by: Thomas Lindroth <thomas.lindroth@xxxxxxxxx> Reported-by: Jan Kara <jack@xxxxxxx> Cc: syzbot <syzbot+c0138741c2290fc5e63f@xxxxxxxxxxxxxxxxxxxxxxxxx> Cc: Ming Lei <ming.lei@xxxxxxxxxx> Cc: Tetsuo Handa <penguin-kernel@xxxxxxxxxxxxxxxxxxx> Cc: Jens Axboe <axboe@xxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/block/loop.c | 2 ++ 1 file changed, 2 insertions(+) --- a/drivers/block/loop.c +++ b/drivers/block/loop.c @@ -1929,10 +1929,12 @@ static long loop_control_ioctl(struct fi break; if (lo->lo_state != Lo_unbound) { ret = -EBUSY; + mutex_unlock(&loop_ctl_mutex); break; } if (atomic_read(&lo->lo_refcnt) > 0) { ret = -EBUSY; + mutex_unlock(&loop_ctl_mutex); break; } lo->lo_disk->private_data = NULL;